Answer:
Tree ring patterns have recently been proven to match up with historical drought records and have revealed everything from changing indigenous forest management in the Central Amazon to the climate patterns that caused ancient Rome to rise and fall.
Explanation:
Answer: 86.47 g of carbon-14 must have been present in the sample 11,430 years ago.
Explanation:
Half-life of sample of carbon -14= 5,730 days
Let the sample present 11,430 years(t) ago = 
Sample left till today ,N= 0.060 g
![ln[N]=ln[N]_o-\lambda t](https://tex.z-dn.net/?f=ln%5BN%5D%3Dln%5BN%5D_o-%5Clambda%20t)
![\log[0.060 g]=\log[N_o]-2.303\times 0.00012 day^{-1}\times 11,430 days](https://tex.z-dn.net/?f=%5Clog%5B0.060%20g%5D%3D%5Clog%5BN_o%5D-2.303%5Ctimes%200.00012%20day%5E%7B-1%7D%5Ctimes%2011%2C430%20days)
![\log[N_o]=1.9369](https://tex.z-dn.net/?f=%5Clog%5BN_o%5D%3D1.9369)
86.47 g of carbon-14 must have been present in the sample 11,430 years ago.
The point on a line through the ends of the meter stick is the electric field equal to zero is 4.7 m from the 0 cm mark.
<h3>What is electric field?</h3>
An electric field is the physical field that surrounds the electrically charged particles and exerts force on all other charged particles in the field, either attracting or repelling them. It also refers to physical field for a system of charged particles. Electric fields originate from the electric charges and time-varying electric currents. Electric fields and the magnetic fields are both manifestations of the electromagnetic field, one of the four fundamental interactions (also called forces) of nature.
Electric fields are important in many areas of the physics, and are exploited in electrical technology. In atomic physics and chemistry, for the instance, the electric field is the attractive force holding the atomic nucleus and electrons together in atoms. It is also force responsible for chemical bonding between atoms that result in molecules.
The electric field is defined as a vector field that associates to each point in the space the (electrostatic or Coulomb) force per unit of charge exerted on an infinitesimal positive test charge at rest at that point. The derived SI unit for electric field is the volt per meter (V/m), which is equal to the newton per coulomb (N/C)
To know more about atoms visit: brainly.com/question/1566330
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The correct question will be:
"A +5.00-μC point charge is placed at 0.0 cm mark of meter stick and a -4.00-μC point charge is placed at 50.0 cm mark. At what point on a line through the ends of meter stick is electric field equal to zero?"
Answer:
Explanation:
First of all, well calculate the spring constant k
K = 2Ei/x^2
Where Ei = initial work required
x = initial stretch length
k = 2×7/0.017^2 = 48443J/m^2
Now work done in stretching it to 5.3cm (1.7 + 3.6) or 0.053m
EF = kx^2/2
48443 × 0.053^2/2 = 68J
Work done in stretching additional 3.6cm is equal to
68J-7J = 61J
